How Do Antennas Work? TV Guide

how do antennas work tv signal radio antenna

Did you know that Heinrich Hertz developed the first dipole antenna in 1886? Since then, technology has come a long way, and now people use it to watch TV and communicate with people all over the world. 

But how do antennas work? What gives them the capability to bring all these videos and audio right to you? 

Keep reading to find out more about how antennas function for television and radio! 

Facts About Antennas 

To understand antenna science, you first have to understand a few facts about antennas. An antenna is a metal device that will either receive or send out radio waves. 

Many electronics have them, like your phone, wireless LAN, TV, radio, radar, or even your GPS. These waves can travel through the air and outer space in order to communicate info. 

Different Types of Antennas 

Each type of antenna is designed to work with a special range of frequencies. Normally, the length or size of the antenna will determine what wavelength, or frequency, that it uses. 

Because of this, each antenna also has its own role. For example, the dipole antenna that we mentioned earlier is just two wires with each end connected to the radio and another end standing in free space. It will receive transmissions from whatever direction it's pointing at. 

On the other hand, a remote display antenna will help transfer waves from the air onto your television so that you can watch TV! 

Antenna Technology 

The antenna that is located on the transmitter will generate a radio wave and send it out over the air. A voltage that is at a specific frequency will then also be applied to the antenna. 

When the voltage cuts across the antenna and into the current, this creates electromagnetic waves. 

When a receiver picks up these waves, it'll create a small voltage and generate whatever the other antenna was sending out. 


The transmission of radio waves is essential to understanding exactly how antennas work. When you send a transmission through an antenna, you generate a magnetic field. This happens when you send an electric current through the antenna. 

Instead of sending out a certain frequency, the antenna will send out signals that are either frequency or amplitude modulated. 

Frequency modulation (FM) and amplitude modulation (AM) are the two most common radio waves, and you've probably had to choose between them when you're trying to find songs on the radio in your car. 


Once the antenna transmits the waves, the radio waves go through the air. Some waves will go straight from the transmitter to the receiver. This is called the line of sight transmission. 

We don't use this anymore, because now we have fiber-optic cables that transmit phone calls. They'll encode the information into a beam of light that's then sent through a glass pipe to a receiving end. 

However, ground waves are another type of travel. Ground waves will go through the space between the earth and the ionosphere to conduct the information, and these are normally what you'll find on AM stations. 

These waves can travel really far, and they're usually at a lower frequency. 


Once the airwaves finishes traveling at the specific wavelength, the antenna you are using will receive the information that the wave is carrying. 

If you receive a signal with information, this is called a carrier signal. When the wave is built up and sent over to your antenna to receive, your antenna will essentially have to "decode it" in order to relay the information back to you. 

For example, this can happen when radio waves are sent through the air to your car's audio system. Once your car's system finishes decoding the different radio waves, it'll be sent through your speaker in the car. However, if you go too far out of range while listening to that radio station, the songs will be difficult to hear and may sound fuzzy. 

This is because sound waves can only travel so far for that radio station. If you're too far and there is nothing else being transmitted on that particular station, you won't be able to hear anything. 

However, you may be able to adjust your system to find a different channel that is broadcasting radio waves near you! 

How Long Does the Antenna Need to Be? 

Most modern radios have at least two antennas. One of them will be a telescopic rod that can pull out and swivel around to reach FM signals. The other rod is normally inside the radio that is fixed on the circuit board. These pick up AM signals. 

The longer antenna is important because it'll affect the certain wavelength that you're going to pick up. However, there are many other factors that will determine what the radio picks up rather than the length of the antenna. 

You'll have to tune the radio to see which signals it is picking up, and the antenna is just in charge of passing the energy from the waves into the circuit board to resonate at the right frequency. 

Learn More About: How Do Antennas Work? 

These are only a few things to know about, "How do antennas work?" However, there are many more things to learn about antenna signals and electronics for television and radio! 

We know that trying to understand all of the new technology that is coming out can be stressful and overwhelming, but we're here to help you out with TV and radio electronics. 

If you enjoyed this article, make sure that you explore our website to find more articles just like this one! Visit the Tech section to learn more about electronics like Antennas, radio, Wi-Fi, GSM, telecommunications, and much more.

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